This invention relates to a new power system. More particularly, this invention pertains to a power system with a cycle in which metallic aluminum is ignited and burned as a synthetic primary fuel in air, or air and water, or other ways, for the production of energy. This system allows the regeneration of the primary fuel through the input of electric energy and the cycle can then be repeated. The energy release per unit weight and volume of the primary fuel compares favorably with conventional fossil fuels.
In today's world, energy is a particularly important concern. The concern is compounded by increasing energy demands and the shortage of certain energy sources. In particular, petroleum and related products, such as fuel oil, natural gas and gasoline have become a major form of energy and are threatening to become more scarce. These products have become extremely important in many ways and one of them is as a mobile or portable fuel or energy supply. Automobiles and other vehicles are dependent on a fuel supply that, by virtue of its characteristics, can be carried with them. The continued availability of petroleum products for this purpose and other applications is becoming a danger area. Thus, there is an important and continuous search for new sources and forms of energy.
Among the usual criteria that are of paramount importance in the consideration of various energy sources are the following: availability of primary ingredients, cost, technology involved, energy yield/weight ratio, environmental considerations, storage considerations, safety considerations and transportability.
Based on the technology of the foreseeable future, one of the most common types of energy in the future that need not be dependent on petroleum proudcts for its generation is expected to be elecricity. Among the various approaches that are in use or are expected to be utilized for the future generation of electricity are: coal, nuclear fission, tides, waves, sun, wind, geothermal, etc. Thus, we can depend on electricity as being available for the foreseeable future.
While electricity is quite likely to satisfy a wide variety of energy demands in the future, it has, so far, been difficult to make extensive use of it as a mobile power source. For such use, energy content per weight and volume of the common electric storage devices has become a limiting criterion.
The present invention with its various embodiments relates to a power system that provides energy through burning a metal and then utilizing electric energy to reconvert the residue back into useable metallic fuel again. Since the metal used as a primary fuel, aluminum, is regenerated or produced from aluminum oxide using electric energy, it may be called a synthetic fuel. In the system, aluminum is burned in air, or in air and water or in other ways for the production of energy. Aluminum oxide and other compounds are formed, depending on the actual reaction utilized. The aluminum oxide can be recycled by the input of electric energy to regenerate metallic aluminum.
An interesting energy conversion cycle is thus achieved, whereby part of the energy used in the electric regeneration of the synthetic fuel is released in other forms with a yield per weight and in volume that compares favorably with fossil fuels. This system, in effect provides a subtle means of "storing" energy during the electric regeneration process of the fuel and allowing its utilization in other form, when required, to power vehicles, or the like, or as described in the various embodiments of this invention. With the input of electric energy for the regeneration of the fuel, the cycle can be repeated.
In the past, aluminum has been proposed for releasing hydrogen and as a possible constituent, among other metals, in systems utilizing other primary fuel material such as lithium or lithium compounds. A system employing aluminum for the generation of hydrogen which in turn is used in a torpedo propulsion system is disclosed in U.S. Pat. No. 3,229,462. It is not believed that aluminum has previously been employed as a primary synthetic fuel for the direct production of power through the system in this invention with the energy conversion cycle earlier described.
Among the apparent positive aspects of this invention are the following:
1--In the power system of this invention, the amount of energy released per unit weight of the fuel when it reacts with oxygen is close to the energy released per unit weight of gasoline when ignited.
2--The energy that can be released per unit volume of the fuel is approximately three times higher than the amount of energy released per unit volume of gasoline burned.
3--Since high temperatures are reached when aluminum burns in air, steam and air/steam combinations, equal or better thermodynamic efficiences may be reached in comparison to oil and gas.
4--Since the fuel in this power system burns in an air/steam combination, high temperature steam may be directly produced and utilized in various ways.
5--Greater amounts of heat can be added to the primary fuel prior to its combustion as compared to fossil fuels.
6--Since aluminum is a metal, when it burns in air, steam and air/steam combinations, the vaporized aluminum in this power system is electrically conducting. As such, it can be advantageously used in magnetohydrodynamic generators (MHD), since the high temperature gas produced is not required to "seed with a metal" as when oil or petroleum is used.
7--While burning in air or steam/air combinations, no uncontrollable environmental pollutants are produced.
8--The oxidized metal residue of the fuel is the main necessary raw material required in preparing the synthetic primary fuel by electricity. The synthetic fuel can be recycled indefinitely, as long as electricity exists.
9--The raw material used in the preparation of the primary fuel is the most abundant metal in the earth's crust.
10--The primary fuel of this invention is easily transportable and non-hazardous during transport, unlike gas, petroleum or hydrogen.
This invention has many applications which by no means are to be understood as being limited to what is herein covered or implied. Among other things, this invention may be utilized in the transportation sector because of the positive aspects described earlier, and particularly, since the primary fuel employed in this invention compares favorably with fuels in power plants operating on the conventional fossil fuels. The fossil fuels are threatening to become scarce and are not regenerated.